﻿using System;
using System.Numerics;
using System.Linq;

class CalculateNFactoriel
{
    static BigInteger CalculateFactoriel(int n)
    {
        if (n==0)
        {
            return 1;
        }
        else
        {
            return n * CalculateFactoriel(n - 1);
        }
    }

    static void Main()
    {
        Console.WriteLine(CalculateFactoriel(100));
    }
}
